A stent delivery system delivers a self-expandable stent to an affected part (lesioned part) to widen a narrow segment or an occluded part occurred in a lumen, such as a blood vessel, of a patient and to releases and deploys the self-expandable stent at a position where the stent is delivered. The stent delivery system includes a delivery catheter configured to include coaxial inner and outer shafts, a self-expandable stent held on a distal part of the delivery catheter in a state in which the stent is reduced in diameter, and an operating handle connected to a proximal part of the delivery catheter (for example, see Patent Literatures 1 to 3, and Non-Patent Literature 1).
Here, the operating handle (for example, “an operating handle 12” in Patent Literature 1, “an operating part 18” in Patent Literature 2, “a controller 10” in Patent Literature 3, and “a handle” in Non-Patent Literature 1) includes a rack and pinion mechanism for linearly converting rotation of a pinion by a rack that engages with the pinion and a thumbwheel for operating the rack and pinion mechanism. The rack and pinion mechanism is configured to include a slide mechanism that moves the outer shaft to a proximal side with respect to the inner shaft during release of the self-expandable stent.